The present invention, in some embodiments thereof, relates to image processing guides and, more particularly, but not exclusively, to image processing guides for head mounted near eye displays (HMNEDs).
The present invention relates to methods and systems for optical configuration and, more particularly, but not exclusively, to an optical configuration having small and thin dimensions for an imaging or non-imaging (afocal or light concentrator) system/s.
In recent years, the demand for high-performance compact optical systems has increased. Some of the optical systems are imaging systems which convey an image of a scene to an image sensor such as a complementary metal-oxide semiconductor (CMOS) based sensor or a charge-coupled device (CCD)-based sensor. Other optical systems (e.g. head mounted displays) convey a digital image from an image source such as a liquid-crystal display (LCD) or liquid-crystal on silicon (LCOS) to create a virtual image to the eye by projecting the digital image directly to the eye. Other optical systems convey a digital image from an image source to a white board or screen, thus projecting a digital image on the screen. Other optical systems, such as binocular or telescopes, just expand or narrow the field-of-view (FOV) of the user. Other optical systems are non-imaging systems used to collect light or to concentrate light into a sensor.
A number of solutions have been developed in order to allow thin and small sized optical systems. For example, U.S. Patent Publication No. 2009/097122 discloses “An optical relay device for transmitting light striking the optical relay device at a plurality of angles within a field-of-view is provided. The device comprises a light-transmissive substrate, an input optical element and an output optical element. The input element diffracts the light to propagate within the light-transmissive substrate via total internal reflection, and the output element diffracts the light out of the substrate. The output element is characterized by planar dimensions selected such that at least a portion of one or more outermost light rays within the field-of-view is directed to a two-dimensional region being at a predetermined distance from the substrate.”
Another example, U.S. Patent Publication No. 2009/097127, discloses “an optical device, including a light-transmitting substrate, optical means for coupling light into the substrate by total internal reflection, and a plurality of partially reflecting surfaces carried by the substrate, characterized in that the partially reflecting surfaces are parallel to each other and are not parallel to any of the edges of the substrate.”
Another example, U.S. Pat. No. 6,805,490, discloses “A planar substrate having a first diffractive element for coupling light waves of different colors into the substrate and guiding the light waves by successive internal reflections. A second diffractive element, disposed on the substrate, causes the guided light waves to be partially transmitted out of the substrate where the light waves encounter the second diffractive element. Because light waves of each color are reflected at different reflection angles, the light waves with smaller reflection angles encounter the second diffractive element at more locations than those with larger reflection angles, resulting in color non-uniformity in the light transmitted out from the substrate surface. One or more interfaces are provided between the surfaces of the substrate to selectively reflect the light waves having larger reflection angles toward the second diffraction element, so that light waves of different colors encounter the second diffraction element substantially at the same number of locations.”
Additional background art includes U.S. Pat. No. 6,351,333, U.S. Pat. No. 6,351,338 and U.S. Pat. No. 6,409,352.